muldi3.c

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/* muldi3.c extracted from gcc-2.7.2.3/libgcc2.c and 
               gcc-2.7.2.3/longlong.h which is: */
/* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#ifdef CONFIG_CPU_HAS_NO_MULDIV64

#define SI_TYPE_SIZE 32
#define __BITS4 (SI_TYPE_SIZE / 4)
#define __ll_B (1L << (SI_TYPE_SIZE / 2))
#define __ll_lowpart(t) ((USItype) (t) % __ll_B)
#define __ll_highpart(t) ((USItype) (t) / __ll_B)

#define umul_ppmm(w1, w0, u, v)                     \
  do {                                  \
    USItype __x0, __x1, __x2, __x3;                 \
    USItype __ul, __vl, __uh, __vh;                 \
                                    \
    __ul = __ll_lowpart (u);                        \
    __uh = __ll_highpart (u);                       \
    __vl = __ll_lowpart (v);                        \
    __vh = __ll_highpart (v);                       \
                                    \
    __x0 = (USItype) __ul * __vl;                   \
    __x1 = (USItype) __ul * __vh;                   \
    __x2 = (USItype) __uh * __vl;                   \
    __x3 = (USItype) __uh * __vh;                   \
                                    \
    __x1 += __ll_highpart (__x0);/* this can't give carry */        \
    __x1 += __x2;       /* but this indeed can */       \
    if (__x1 < __x2)        /* did we get it? */            \
      __x3 += __ll_B;       /* yes, add it in the proper pos. */    \
                                    \
    (w1) = __x3 + __ll_highpart (__x1);                 \
    (w0) = __ll_lowpart (__x1) * __ll_B + __ll_lowpart (__x0);      \
  } while (0)

#else

#define umul_ppmm(w1, w0, u, v) \
  __asm__ ("mulu%.l %3,%1:%0"                       \
           : "=d" ((USItype)(w0)),                  \
             "=d" ((USItype)(w1))                   \
           : "%0" ((USItype)(u)),                   \
             "dmi" ((USItype)(v)))

#endif

#define __umulsidi3(u, v) \
  ({DIunion __w;                            \
    umul_ppmm (__w.s.high, __w.s.low, u, v);                \
    __w.ll; })

typedef      int SItype __attribute__ ((mode (SI)));
typedef unsigned int USItype    __attribute__ ((mode (SI)));
typedef      int DItype __attribute__ ((mode (DI)));
typedef int word_type __attribute__ ((mode (__word__)));

struct DIstruct {SItype high, low;};

typedef union
{
  struct DIstruct s;
  DItype ll;
} DIunion;

DItype
__muldi3 (DItype u, DItype v)
{
  DIunion w;
  DIunion uu, vv;

  uu.ll = u,
  vv.ll = v;

  w.ll = __umulsidi3 (uu.s.low, vv.s.low);
  w.s.high += ((USItype) uu.s.low * (USItype) vv.s.high
           + (USItype) uu.s.high * (USItype) vv.s.low);

  return w.ll;
}